I blame all forms of theism for this. Ignorance, willful or otherwise, and self delusion, are at the heart of why these things happen.

If people stopped believing in made up nonsense the world could move on and prosper.

Further, and once again, just because party A refers to party B as a Satanist (especially as an insult or way to disparage their character) does not mean that party B is a Satanist. A Satanist is described in the Satanic Bible by LaVey.